1. Field of the Invention
The present invention relates to a contact lens material having an antibacterial property, in which an antibacterial ceramic containing at least one metal selected from the group consisting of Ag, Cu and Zn is mixed with or coated onto a hydrogel lens material.
2. Description of the Prior Art
It is well known that contact lenses can be used instead of a pair of spectacles. A hard contact lens comprising polymethacrylic acid methyl esters as a main component, a soft contact lens comprising poly 2-hydroxy ethyl methacrylate as a main component, or a contact lens comprising natural polymers such as collagen, glass or ceramics are known.
When a contact lens is fitted to a cornea, a thin film of tear fluid remains between the lens and the cornea. Further, the outer surface of the contact lens is in contact with the atmosphere. The lens once installed on the eye is likely to be attacked by undesired materials such as bacteria and dust in the air and entails breeding of bacteria along the surfaces of the contact lens so that a risk occurs of developing a surface injury to the eye. Also it is necessary that a supply of fresh air be available to the cornea beneath the contact lens to promote metabolism of the cornea tissues. For these reasons, various materials have been examined as suitable contact lens materials. However, materials that allow a supply of fresh air to the cornea to prevent cornea damage and that exclude undesired materials have not heretofore been found.